The present invention relates to an indexing device for storing telephone numbers and other information for retrieval, the device being easy to handle, reliable in action and easy to manufacture.
In most of the conventional indexing devices, letters of an alphabet are carried on the cover extending over the cards; a guide slit is provided near the position of these letters; an operator which partly goes into the guide slit is movable in relation to the cover; a slider is integrally attached to the operator; and using the slider, the device can be opened to lift the cards to expose a card matching the position of the operator.
In such indexing devices, the operation is cumbersome with two steps required, i.e., setting the operator to a specific letter on the cover, and opening the cover by unlocking the cover from the base by pressing a button on the base.
An operator designed as a push-button mechanism in which the opening of the cover and the selection of a card can be done in one action is disclosed in the U.S. Pat. No. 3,073,049 (TELEPHONE INDEX), U.S. Pat. No. 2,960,781 (MULTIPLE CARD INDEX), U.S. Pat. No. 2,849,815, U.S. Pat. No. 2,329,300 (BOOK CONSTRUCTION), etc.; this operator has, however, the drawback that it is liable to pick up an unwanted card or cards together with the wanted one when the button is pressed. The U.S. Pat. No. 2,849,815 discloses a device which has a U-shaped piece to hold cards to the cover. However, since the U-shaped piece is spring-urged in one direction, many parts are needed to hold the card. Thus the device is complicated and in addition, the U-shaped piece has a middle part as wide as the front wall. Unwanted pickup frequently occurs when a selected card is lifted rapidly because of negative air pressure or suction between the lifted cards and the remaining cards of the stack. The present invention avoids this phenomenon.